Lubricant composition



Patented Oct. 17, 1950 2,526,490 LUBRICANT COMPOSITION Eugene Lieber,Chicago, Ill., assignor to Standard mpany, a corporation of OilDevelopment Co Delaware No Drawing. Application December 12, 1946,

Serial 8 Claims. (Cl. 252-52) This invention .relates to a novel type ofcondensation product and to methods of preparing such products and usingthem for various purposes, more particularly as pour depressors in waxylubricating oils.

A pour depressor is asubstance capable of lowering the temperature atwhich a hydrocarhon oil comprising a substantially homogeneous mixtureof liquid hydrocarbons and waxy solids undergoes loss of fluidity. Theexpression pour point is used herein to mean the pour point asdetermined by the standard A. S. T. M. method.

Certain heavy-alkyl substituted aromatic hydrocarbon products are knownto be pour depressors. It has also been proposed to improve such pourdepressors by a subsequent resinification reaction, emphasizing the useof heavyalkyl substituted aromatics by describing them as being made bycondensation of aromatic hydrocarbons with chlorinated aliphatichydrocarbons of relatively high molecular weightespecially the parafiinwaxes. It should be pointed out that the heavy-alkyl substitutedaromatics used as starting materials in that process are in themselvespour depressors for lubricating oils.

On the other hand, it has also been suggested that pour depressors canbe prepared by first resinifying an aromatic hydrocarbon and thenalkylating the resultant product by condensing it with chlorinated highmolecular weight aliphatic hydrocarbon material such as paraflln wax.

It has now been discovered, and is the primary feature of the presentinvention, that powerful and novel wax modifying agents useful particularly as pour depressors for waxy oils can be prepared which compriseessentially a reaction product of an aromatic compound, a resinifyingagent capable of resinifying said aromatic compound, and a condensablealiphatic hydrocarbon compound of low molecular weight preferably havingless than '7 carbon atoms. This result is distinctly unexpected andcontrary to the above and many other teachings of the prior art.

This application a continuation-in-part of Ser. No. 469,579, filedDecember 19, 1942 (now Patent No. 2,412,589), which is acontinuationin-part of Ser. No. 354,144, filed August 24, 1940, nowPatent 2,384,107.

The above applications disclose that the purposes of this invention canbe accomplished in several diflerent ways, depending essentially uponthe order of reacting the several raw materials. According to onemethod, which for the sake of simplicity will be referred to as methodA, the low molecular weight aliphatic hydrocarbon groups are firstcondensed with an arcmatic compound to make an alkylated aromaticcompound having at least one alkyl substituent group containing lessthan '7 carbon atoms, and subsequently resinifying said product bytreatment with a suitable resiniiylng agent, as for instance analdehyde. 0n the other hand, according to method B, the aromaticcompound is first resinified, as by reaction with an aldehyde, and thenthe resulting product is alkylated with a low molecular weight aliphatichydrocarbon group containing less than '7 carbon atoms, as, forinstance, by condensation with amyl chloride. It should be understoodthat no invention is claimed herein as to the first step 0! eithermethod A or B but only in making the final reaction product. A thirdmethod C comprises simultaneous reaction of all three separateconstituents, i. e., an aromatic compound, a resinii'ying agent capableof resiniiying said aromatic compound, and a condensable aliphatichydrocarbon compound of low molecular weight, preferably having lessthan '7 carbon atoms.

That the invention obtains new and unexpected results is clear from thefact that in method A the alkylated aromatic compound to be resinifieddoes not per se have any substantial pour depressing properties, andonly attains such properties as a result of the subsequentresiniflcation. 0n the other hand, in method B the resinified aromaticcompound first formed is likewise not a pour depressor and in some casesis not even soluble in mineral oil, and the desired characteristics ofsuitable oil-solubility and pour depressing properties are not imparteduntil the subsequent alkylation. In the earlier applications mentionedabove, the claims are limited to the use of hydrocarbons as the type ofaromatic raw material. In process B, the reaction of phenol withtrioxymethylene gave a resinified product too insoluble to permitalkylation; and the reaction of aniline with trioxymethylene gave aresinified product which. even when alkylated with amyl chloride, didnot have pour depressing properties. However, as disclosed and claimedherewith, process A can be successfully applied to hydroxy-aromatic(phenolic) raw materials.

An outstanding advantage of the present invention is that the lowmolecular weight aliphatic hydrocarbon compounds used in preparing theproducts of this invention are available in large, substantially limitles, quantity and at relatively low cost; whereas the high molecularweight aliphatic compounds used heretofore are available only inrelatively limited quantities and at a cost which at times is relativelyhigh, in view of the great demand for such high molecular weightproducts in other fields.

The aromatic compounds to be used according to the present invention maycomprise only one or mixtures of a number of different types ofmonomeric mono-, diand other poly-nuclear aromatic hydroxy compoundsthereof capable of being resinified by the resinifying agents to bementioned further on. Some specific examples of suitable aromaticcompounds are phenol, cresol, alphaand beta-naphthol, petroleum phenols,and the like.

The low molecular weight condensable aliphatic hydrocarbon compounds tobe used may be selected from the group consisting of the aliphatichalides, especially the mono-halogen substituted aliphatic hydrocarbons,or olefins corresponding thereto, such as would be obtained bydehydrohalogenation thereof. Specific examples are amyl chloride, hexylchloride, butyl chloride, isobutyl chloride, and even lower alkylhalides, such as the proypl, especially isopropyl, or other branchedalkyl chlorides, although it is preferred to use those having from 4 to6 carbon atoms.

Although the halogen substituent is preferably chlorine from practicalconsiderations, the other corresponding halides may be used such asbromides and iodides, the fluorides being in most cases somewhat toostable to give the desired reaction. Instead of using any singlecompound, mixtures of two or more may be used, such as the mixed amylchlorides available on the market as a commercial product, comprisingessentially a mixture of primary, secondary and tertiary amyl chlorides;or other mixed products such as the chlorides obtained by simultaneouschlorination of a mixture of hydrocarbon gases containing 4, 5 and 6carbon atoms.

The resinifying agents to be used according to the present invention maybe those which are already known to the art, including particularly thealdehydes, such as formaldehyde, or products comprising the same, suchas tri-oxymethylene, or others such as acetaldehyde, propanaldehyde andthe like, or other types of resinifying agents, such as sulfur halides,elementary sulfur, and so forth.

In carrying out the invention according to method A, the alkylatedaromatic compound to be used may either be obtained as such from asuitable source or may be manufactured especially for the purposes ofthis invention, in which case suitable aromatic hydroxy compounds, suchas those mentioned above, should be condensed with a suitable lowmolecular weight aliphatic hydrocarbon compound, such as amyl chlorideor amylene, preferably by use of a Friedel-Crafts condensing agent, e.g., aluminum chloride, boron fluoride, zinc chloride, ferric chloride,titanium tetrachloride, boron trichloride, and so forth; or, in somecases anhydrous hydrogen fluoride or mixtures thereof or sulfuric acidor other alkylating agent. The alkylation may be effected by knownmethods.

The final condensation or resinification of the alkylated hydroxyaromatic compound with the resinifying agent e. g. formaldehyde, iscarried out in the presence of an inert solvent or diluent, such as arefined naphtha or kerosene, or a chlorinated hydrocarbon compound, suchas tetrachlorethane, dichlorbenzene, or others such as carbon disulfide,nitrobenzene, and so forth; the

amount thereof should be about one-half o .ive-

times the volume of the reactants. The re: :tion may, if desired bestarted at room temperature but thefinal reaction temperature should beabout 125 F. to 300 F., preferably about 150 to 200 F. The time ofreaction varies inversely witl. the temperature used and should be aboutone-half to five hours, preferably one to two hours, preferably withAlCla catalyst.

After the Friedel-Crafts condensation has been completed, the reactionmixture is cooled, preferably diluted with an inert liquid such as arefined kerosene, and neutralized by pouring into a mixture of alcoholand water. After settling, the kerosene extract is distilled to removeunreacted raw materials and to obtain the desired resinified alkylatedaromatic hydroxy compound as a distillation residue.

Although aluminum chloride is the preferred catalyst for theresinification, other condensation catalysts may be used under somecircumstances, e. g. zinc chloride, sulfuric acid, phosphoric acid,phosphoric anhydride, acetic acid, etc. The amount of catalyst to beused varies according to the nature and quantities of reactants used andalso depends to some extent upon the quality and quantity of productdesired, the yield being generally directly proportional to the amountof catalyst used, up to a certain optimum amount, decreasing graduallytherefrom. The amount of catalyst should normally be about 10 to 150,preferably about 20 to 100 parts by weight per 100 parts by weight ofalkylated aromatic hydroxy compound used. Sometimes products having themost potent pour-depressing effects are produced under conditions givingrelatively small yields, but this is not always true.

The final reaction product is recovered by distilling off the lowboiling constituents thereof and from solution in a suitable inertsolvent such as highly refined kerosene, by distillation under reducedpressure, e. g., with fire and steam, 0: under vacuum at an absolutepressure as low as 100 mm., preferably as low as 20 mm. mercury, toabout 600 F., leaving as a distillation residue the desired reactionproducts having wax modifying properties.

The reaction product of this invention is usually a more or less brittleresin, ranging from a yellowish to a dark-brown color, althoughsometimes it has a greenish color, and in a few instances it is more ofa viscous oil than a solid. Many of the phenolic-aldehyde condensationresins made heretofore have been either completely insoluble in commonsolvents, or, if soluble at all in hydrocarbon oils, only soluble inaromatic and naphthenic hydrocarbon oils, and substantially insoluble inhighly parafllnic oils. Therefore, it is quite surprising that thephenolic-aldehyde resins of the present invention have good solubilityin paraflinic mineral lubricating oils.

The product of this invention has the property of modifying the crystalstructure of waxes such as parafiin wax present when added tocompositions containing same. For instance, when about .05-10.0%,preferably 0.2-5.0%, of this wax modifier is added to a waxy lubricatingoil such as a Pennsylvania type lubricating oil having a relatively highpour point, the resultant blend will have a substantially lower pourpoint; in other words, this wax modifier is an effective pour depressorfor waxy oil. A small amount of this wax modifier is also useful as adewaxing aid for removing wax from mineral lubricating oils ofundesirably high wax content. In similarly small amounts, this waxmodifier may also be incorporated into parafiln wax or compositionscontaining the same to be used for various purposes such as for coatingor impregnating paper, etc. or for making various molded products.

The proportions in which the various raw materials should be combined tomake the novel wax modifying agents of this invention, vary to asubstantial extent as indicated in the following experimental example,but in general it may be said that for one mole of aromatic compound,one-half to five moles of low molecular weight aliphatic hydrocarboncompounds should be used and about one-half to two moles of theresinifying agent.

The invention will be better understood from a consideration of thefollowing example, which is given for illustration only.

Example 165 grams of tertiary amyl phenol and 32 grams oftrioxymethylene were suspended in 200 cc. of o-dichlorbenzene. 20 gramsof anhydrous aluminum chloride were then added to the reaction mixturewith suitable agitation. After the addition of the AlCls, thetemperature was increased to 175 F. and maintained thereat for one hour.After cooling, the reaction mixture was diluted with 500 cc. further ofkerosene and neutralized by pouring into a mixture of alcohol and water.After settling, the kerosene extract was distilled with fire and steamto 600 F. in order to remove solvent and low-boiling products. A bottomsresidue comprising 144 grams of a brown brittle resin was obtained asproduct.

When this resinification product was added in various amounts to a waxylubricating oil, the A. S. T. M. pour point of which was 25 F., the

resulting blends had the following pour points:

gf Pour Point Thus according to the present invention, a low molecularweight alkyl aromatic hydroxy compound, such as t-amyl phenol, which perse has no pour-depressing properties, is converted by resinification aswith tri-oxymethylene, into a pour depressor having good solubility inwaxy lubricating oils.

It is not intended that this invention be limited to any of the specificexamples which were given merely for the sake of illustration nor to anytheory as to the mechanism of the operation 01' the invention but onlyby the appended claims in which it is int nded to claim allmodifications coming within e scope and spirit of the invention.

It is claimed;

1. A product having good solubility in highly parafllnic min'erallubricating oil, said product consisting essentially of a resin producedby resinification of one mole of an alkyl phenol having 4 to 6 carbonatoms in the alkyl group, with about /2 to 2 moles of a lower saturated.aliphatic aldehyde having 1 to 3 carbon atoms, in the presence of to 5volumes of inert solvent per volume 0! reactants, and in the presence ofabout 10 to 150 parts by weight of aluminum chloride catalyst per partsby weight of alkyl phenol, using a final reaction temperature of F. to300 F., said resin being substantially non-volatile under reducedpressure up to 600 F.

2. The process which comprises resinifying 1 mol of an alkyiated hydroxyaromatic hydrocarbon compound not having any substantial pourdepressingproperties and containing an alkyl group having from 3 to 6 carbonatoms, with to 2 mols of an aldehyde serving as resinifying agent having1 to 3 carbon atoms, in the presence of a Friedel-Crafts catalyst, andin the presence of an inert solvent, at a temperature between theapproximate temperature of room temperature and 300 F., separating thecatalyst from the reaction product and subjecting the said reactionproduct to distillation under reduced pressure to 600 F. to obtain thedesired pour depressor as distillation residue.

3. The process for making pour depressors for waxy lubricating oilswhich comprises resinifying one mole of an alkyl phenol having 4 to 6carbon atoms in the alkyl group, with about V2 to 2 moles of a saturatedaliphatic aldehyde having 1 to 3 carbon atoms, in the presence of aboutto 5 volumes of inert solvent per volume of reactants, and in thepresence of about 10 to parts by weight of aluminum chloride catalystper 100 parts by weight of alkyl phenol, using a final reactiontemperature of about 125 to 300 F., hydrolyzing and removing thecatalyst and subjecting the reaction products to fire and steamdistillation up to 600 F. to obtain the desired resinous pour depressoras distillation residue.

4. Process according to claim 6 using an amyl phenol andtrioxymethylene.

5. Process according to claim 6 using about one mole of tertiary amylphenol and about one mole of trioxymethylene, and using a reactiontemperature of F.

6. A lubricating oil composition consisting essentially of a majorproportion of a waxy mineral lubricating oil having dissolved therein apour-depressing amount of an oil-soluble brittle resin made byresinification of about one mole of tertiary amyl phenol with about onemole of trioxymethylene in the presence of about A to 5 volumes of inertsolvent per volume of reactants and in the presence of about 20 to 100parts by weight of aluminum chloride per 100 parts by weight of tertiaryamyl phenol, using a resinification temperature of about 175 F.,followed by hydrolysis and removal of the catalyst and distillation ofthe reaction products with fire and steam up to about 600 F. to obtainthe desired pour depressor as distillation residue.

'7. An oil-soluble product consisting essentially of a material producedby the resinification of 1 mol of a monomeric hydroxy aromatichydrocarbon contalning an alkyl group having from 3 to 6 carbon atoms inthe alkyl group with about /2 to 2 mols of a lower saturated aliphaticaldehyde having 1 to 3 carbon atoms in the presence of about 10 to 150parts by weight of a Friedel- Crafts catalyst per 100 parts of aromaticcompound.

8. A composition consisting essentially of a major proportion of a waxymineral lubricating oil and a small but pour depressing amount of amaterial produced by aldehyde resinification oi 1 mol of an alkylatedhydroxy aromatic hydrocarbon not per se having any substantial pourdepressing properties and containing an alkyl group 7 8 having from 3 to6 carbon atoms with about UNITED STATES PATENTS to 2 mols of an aldehydehaving 1 to 3 carbon atoms in the presence of about 10 to 150 parts g TZby weight of a Friedel-Crafts catalyst per 100 2062676 Rem i"; 1936parts by weight of said aromatic compound. 5 2:072:12) za'g 1937 EUGENELIEBER. 2,173,346 Turklngton et a1. Sept. 19, 1939 FOREIGN PATENTSREFERENCES CITED Number Country Date The following references are ofrecord in the 10 406,686 France Dec. 14, 1909 file of this patent:375,638 Great Britain May 16, 1923

1. A PRODUCT HAVING GOOD SOLUBILITY IN HIGHLY PARAFFINIC MINERALLUBRICATING OIL, SAID PRODUCT CONSISTING ESSENTIALLY OF A RESIN PRODUCEDBY RESINIFICATION OF ONE MOLE OF AN ALKYL PHENOL HAVING 4 TO 6 CARBONATOMS IN THE ALKYL GROUP, WITH ABOUT 1/2 TO 2 MOLES OF A LWER SATURATEDALIPHATIC ALDEHYDE HAVING 1 TO 3 CARBON ATOMS, IN THE PRESENCE OF 1/2 TO5 VOLUMES OF INERT SOLVENT PER VOLUME OF REACTANTS, AND IN THE PRESENCEOF ABOUT 10 TO 150 PARTS BY WEIGHT OF ALUMINUM CHLORIDE CATALYST PER 100PARTS BY WEIGHT OF ALKYL PHENOL, USING A FINAL REACTION TEMPERATURE OF125*F. TO 300*F., SAID RESIN BEING SUBSTANTIALLY NON-VOLATILE UNDERREDUCED PRESSURE UP TO 600*F.
 8. A COMPOSITION CONSISTING ESSENTIALLY OFA MAJOR PROPORTION OF A WAXY MINERAL LUBRICATING OIL AND A SMALL BUTPOUR DEPRESSING AMOUNT OF A MATERIAL PRODUCED BY ALDEHYDE RESINIFICAITONOF 1 MOL OF AN ALKYLATED HYDROXY AROMATIC HYDROCARBON NOT PER SE HAIVNGANY SUBSTNATIAL POUR DEPRESSING PROPERTIES AND CONTAINING AN ALKYL GROUPHAVING FROM 3 TO 6 CARBON ATOMS WITH ABOUT 1/2 TO 2 MOLS OF AN ALDEHYDEHAVING 1 TO 3 CARBON ATOMS IN THE PRESENCE OF ABOUT 10 TO 150 PARTS BYWEIGHT OF A FRIEDEL-CRAFTS CATALYST PER 100 PARTS BY WEIGHT OF SAIDAROMATIC COMPOUND.